---How long have you been in this office?
---Just a few minutes. My cousins _______ here together with me.
| A．have walked | B．had walked | C．walked | D．have been walking |
—It’s a lovely day, isn’t it?
—Yes, I love ___.
| A．This |
| B．That |
| C．It |
| D．One |
We’d very much appreciate ___ if you could help us.
| A．this |
| B．that |
| C．it |
| D．you |
—Keep ___ in mind that you have to be here on time.
—OK, I will.
| A．it |
| B．me |
| C．this |
| D．one |
The public ___ of the environmental problem will make the government take it seriously.
| A．existence |
| B．revolution |
| C．awareness |
| D．evidence |
Try on both shoes and walk around to ensure a comfortable fit ___ you know your shoe size.
| A．as if |
| B．unless |
| C．even if |
| D．now that |